With an average speed of 3.5 mph, the crosstown M50 is barely faster than a pedestrian’s typical 3.1 mph speed.

Figuring in the wait time, a crosstown rider in decent health is better off just hoofing it.

“You could certainly walk faster than this bus goes,” said Gene Russianoff, the chief Straphanger.

“This is the slowest bus ever! Half the time it doesn’t even come. It’s definitely the worst bus I’ve ever been on,” said regular M50 rider Lewis Morris, 39.

Three Manhattan buses — the M101, M102 and M103 — shared the Straphangers’ annual Schleppie Award as the buses most likely to run bunched up or with big gaps.

The three lines share the same trunk route along Third and Lexington avenues to connect different points uptown and downtown.

Speed and schedule issues aren’t the only problem with NYC Transit’s creaking bus system — mechanical breakdowns are increasing and the number of buses 12 years old or older has doubled in the last year.

But there’s at least one bright spot: Select Bus service along First and Second avenues in Manhattan and on the Bx12 line in the Bronx runs faster than local buses, the Straphangers say.

Riders must buy tickets before they board Select Buses, which are designed for faster boarding and run in exclusive lanes. More Select Bus service is planned in Manhattan, Brooklyn and Staten Island.